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From: archetyp@uxh.cso.uiuc.edu (Joseph R Pickert)
Newsgroups: comp.os.minix
Subject: Re: MacMinx: Serial ports & Multifinder (Q:)
Message-ID: <1990Oct31.190050.5491@ux1.cso.uiuc.edu>
Date: 31 Oct 90 19:00:50 GMT
References: <35041@nigel.ee.udel.edu>
Sender: news@ux1.cso.uiuc.edu (News)
Organization: University of Illinois at Urbana
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worrall@freezer.it.udel.edu (Robert Worrall) writes:

>I am running MacMinix on a IIci 4/105 with system 6.0.7.  I find that Minix
>takes over the serial ports when I boot it and I am unable to sustain my
>network or modem connections.  I understand that it is good for Minix to 
>be able to access these serial ports but is there a way to disable Minix from 
>requesting the ports so I can do serial IO with another multifinder process?
>BTW: the result of accessing the serial ports when minix is active is a hard
>crash on my system.

The serial lines are opened with OpenDriver calls, which should fail when
the port is already in use by another application (at least this is the
way I read the documentation), and a little message should occur in the
console window saying the opendriver failed.  Now this seems to work
when I specifiy that appletalk is being used on one of the ports (i.e., MINIX
wont use that port and I get a little message). However, when I started
Macintosh Kermit first, and then started MINIX, I didn't get a message,
so either 1) I misunderstood the rules for using the ports, or 2) some
other apps aren't following the rules. Probably #1.

As to your problem, in the short term you could turn on appletalk on the
port you want to use, then start minix, then turn appletalk off and start
your serial line app (can you say hack?).  A better solution is to rebuild
kernel with NR_RS_LINES == 0. An even better solution would probably be to
eventually put it in the configuration dialog box.

Joe Pickert